1,098 research outputs found

    Aircraft-based observations of air–sea turbulent ïŹ‚uxes around the British Isles

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    Observations of turbulent ïŹ‚uxes of momentum, heat and moisture from low-level aircraft data are presented. Fluxes are calculated using the eddy covariance technique from ïŹ‚ight legs typically ∌40 m above the sea surface. Over 400 runs of 2 min (∌12 km) from 26 ïŹ‚ights are evaluated. Flight legs are mainly from around the British Isles although a small number are from around Iceland and Norway. Sea-surface temperature (SST) observations from two on-board sensors (the ARIES interferometer and a Heimann radiometer) and a satellite-based analysis (OSTIA) are used to determine an improved SST estimate. Most of the observations are from moderate to strong wind speed conditions, the latter being a regime short of validation data for the bulk ïŹ‚ux algorithms that are necessary for numerical weather prediction and climate models. Observations from both statically stable and unstable atmospheric boundary-layer conditions are presented. There is a particular focus on several ïŹ‚ights made as part of the DIAMET (Diabatic inïŹ‚uence on mesoscale structures in extratropical storms) project. Observed neutral exchange coefïŹcients are in the same range as previous studies, although higher for the momentum coefïŹcient, and are broadly consistent with the COARE 3.0 bulk ïŹ‚ux algorithm, as well as the surface exchange schemes used in the ECMWF and Met OfïŹce models. Examining the results as a function of aircraft heading shows higher ïŹ‚uxes and exchange coefïŹcients in the across-wind direction, compared to along-wind (although this comparison is limited by the relatively small number of along-wind legs). A multi-resolution spectral decomposition technique demonstrates a lengthening of spatial scales in along-wind variances in along-wind legs, implying the boundary-layer eddies are elongated in the along-wind direction. The along-wind runs may not be able to adequately capture the full range of turbulent exchange that is occurring because elongation places the largest eddies outside of the run length

    Analytical modeling of micelle growth. 2. Molecular thermodynamics of mixed aggregates and scission energy in wormlike micelles

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    Hypotheses: Quantitative molecular-thermodynamic theory of the growth of giant wormlike micelles in mixed nonionic surfactant solutions can be developed on the basis of a generalized model, which includes the classical phase separation and mass action models as special cases. The generalized model describes spherocylindrical micelles, which are simultaneously multicomponent and polydisperse in size. Theory: The model is based on explicit analytical expressions for the four components of the free energy of mixed nonionic micelles: interfacial-tension, headgroup-steric, chain-conformation components and free energy of mixing. The radii of the cylindrical part and the spherical endcaps, as well as the chemical composition of the endcaps, are determined by minimization of the free energy. Findings: In the case of multicomponent micelles, an additional term appears in the expression for the micelle growth parameter (scission free energy), which takes into account the fact that the micelle endcaps and cylindrical part have different compositions. The model accurately predicts the mean mass aggregation number of wormlike micelles in mixed nonionic surfactant solutions without using any adjustable parameters. The endcaps are enriched in the surfactant with smaller packing parameter that is better accommodated in regions of higher mean surface curvature. The model can be further extended to mixed solutions of nonionic, ionic and zwitterionic surfactants used in personal-care and house-hold detergency

    Challenging behaviour in dementia care: A novel framework for translating knowledge to practice

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    This article provides guidance on the management of challenging behaviours (CBs) in dementia care, and introduces concepts from positive behavioural support not usually applied to dementia. While the use of formulations has received a lot of attention in recent years, the mechanisms of how to apply the formulation-led interventions requires more consideration. In order to assist caregivers to deliver effective interventions we need to have a better understanding of the CBs we are attempting to manage, and also produce management strategies with clearer goals. Ideally we would also want caregivers to be able to describe the skills they employ in a coherent manner in order to facilitate selfreflection and to be able to pass on their skills to junior colleagues. This paper attempts to fulfil these needs by integrating two new models with philosophies already used in dementia care. In terms of new concepts, the first is the Arousal Cycle, which gives caregivers an awareness of the five phases of a typical CB (wellbeing, trigger, escalation, CB, and recovery phase). In relation to the second, the Traffic Light analogy examines CBs in terms of four management stages: Primary prevention, secondary prevention, reactive strategies, and calming strategies. It is proposed that we distinguish between these stages when composing our formulations and care plans, and thereby produce better targeted interventions. By the end of the paper the reader will have been presented with material integrating concepts from the fields of dementia and intellectual impairment, and been introduced to new ways of managing CBs

    UK clinicians’ views on the use of formulations for the management of BPSD: a multidisciplinary survey

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    © 2020 Informa UK Limited, trading as Taylor & Francis Group. Background and objectives: The process of formulating in the area of dementia care is at an early stage of development. A review published in 2016, identified 14 different types of formulation-based approaches for the management of Behavioural and Psychological Symptoms of Dementia (BPSD). The present study examines professionals’ views about the use of systematic formulations for choosing first-line non-pharmacological interventions for BPSD. Methods: A 34-item online survey, with six items about formulation-based interventions for the management of BPSD, was circulated to multi-disciplinary UK dementia networks. Quantitative data were examined for the use of formulation-based frameworks in practice. Thematic analyses provided insight into the practicalities of using formulations. Results: The majority of the 355 participants responding to the questions stated they used formulation-led models to inform interventions, but 24% stated they did not. Thirty-two types of formulation frameworks were named, and there was a diverse spread across the UK. The Newcastle model was the most frequently used framework, with fifty percent of the participants who formulated reporting using this framework. Four themes regarding the use of formulation emerged, relating to function, process, reported outcomes and obstacles. Conclusion: Formulation-based approaches to targeting intervention are becoming popular in dementia care in the UK. More types of formulation frameworks are used in practice compared with the 2016 review. The use of formulations are seen as key to offering an alternative to pharmacological treatments. Understanding both the value of formulation-led approaches and the obstacles to their use are important to implementing NICE 2018 recommendations

    A new paradigm for the prediction of antidepressant treatment response

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    Current treatment of Major Depressive Disorder utilizes a trial-and-error sequential treatment strategy that results in delays in achieving response and remission for a majority of patients. Protracted ineffective treatment prolongs patient suffering and increases health care costs. In addition, long and unsuccessful antidepressant trials may diminish patient expectations, reinforce negative cognitions, and condition patients not to respond during subsequent antidepressant trials, thus contributing to further treatment resistance. For these reasons, it is critical to identify reliable predictors of antidepressant treatment response that can be used to shorten or eliminate lengthy and ineffective trials. Research on possible endophenotypic as well as genomic predictors has not yet yielded reliable predictors. The most reliable predictors identified thus far are symptomatic and physiologic characteristics of patients that emerge early in the course of treatment. We propose here the term “response endophenotypes” (REs) to describe this class of predictors, defined as latent measurable symptomatic or neurobiologie responses of individual patients that emerge early in the course of treatment, and which carry strong predictive power for individual patient outcomes. Use of REs constitutes a new paradigm in which medication treatment trials that are likely to be ineffective could be stopped within 1 to 2 weeks and other medication more likely to be effective could be started. Data presented here suggest that early changes in symptoms, quantitative electroencephalography, and gene expression could be used to construct effective REs. We posit that this new paradigm could lead to earlier recovery from depressive illness and ultimately produce profound health and economic benefits

    Blockade of collagen-induced arthritis post-onset by antibody to granulocyte-macrophage colony-stimulating factor (GM-CSF): requirement for GM-CSF in the effector phase of disease

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    There is mounting evidence for a role of the growth factor granulocyte-macrophage colony-stimulating factor (GM-CSF) in inflammatory disease, including arthritis. In the present study, we examined the effectiveness of treatment of collagen-induced arthritis (CIA) with a neutralizing mAb to GM-CSF. DBA/1 mice were immunized for the development of CIA and treated at different times, and with different doses, with neutralizing mAb to GM-CSF or isotype control mAb. Anti-GM-CSF mAb treatment prior to the onset of arthritis, at the time of antigen challenge, was effective at ameliorating the ensuing disease. Modulation of arthritis was seen predominantly as a reduction in overall disease severity, both in terms of the number of limbs affected per mouse and the clinical score of affected limbs. Importantly, anti-GM-CSF mAb treatment ameliorated existing disease, seen both as a reduction in the number of initially affected limbs progressing and lower numbers of additional limbs becoming affected. By histology, both inflammation and cartilage destruction were reduced in anti-GM-CSF-treated mice, and the levels of tumor necrosis factor-a and IL-1? were also reduced in joint tissue washouts of these mice. Neither humoral nor cellular immunity to type II collagen, however, was affected by anti-GM-CSF mAb treatment. These results suggest that the major effect of GM-CSF in CIA is on mediating the effector phase of the inflammatory reaction to type II collagen. The results also highlight the essential role of GM-CSF in the ongoing development of inflammation and arthritis in CIA, with possible therapeutic implications for rheumatoid arthritis

    Landscapes of Settlement in Northern Iceland: Historical Ecology of Human Impact and Climate Fluctuation on the Millennial Scale

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    Early settlement in the North Atlantic produced complex interactions of culture and nature. The sustained program of interdisciplinary collaboration is intended to focus on ninth- to 13th-century sites and landscapes in the highland interior lake basin of MÂŽyvatn in Iceland and to contribute a long-term perspective to larger issues of sustainable resource use, soil erosion, and the historical ecology of global change

    Yoga as a Complementary Treatment of Depression: Effects of Traits and Moods on Treatment Outcome

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    Preliminary findings support the potential of yoga as a complementary treatment of depressed patients who are taking anti-depressant medications but who are only in partial remission. The purpose of this article is to present further data on the intervention, focusing on individual differences in psychological, emotional and biological processes affecting treatment outcome. Twenty-seven women and 10 men were enrolled in the study, of whom 17 completed the intervention and pre- and post-intervention assessment data. The intervention consisted of 20 classes led by senior Iyengar yoga teachers, in three courses of 20 yoga classes each. All participants were diagnosed with unipolar major depression in partial remission. Psychological and biological characteristics were assessed pre- and post-intervention, and participants rated their mood states before and after each class. Significant reductions were shown for depression, anger, anxiety, neurotic symptoms and low frequency heart rate variability in the 17 completers. Eleven out of these completers achieved remission levels post-intervention. Participants who remitted differed from the non-remitters at intake on several traits and on physiological measures indicative of a greater capacity for emotional regulation. Moods improved from before to after the yoga classes. Yoga appears to be a promising intervention for depression; it is cost-effective and easy to implement. It produces many beneficial emotional, psychological and biological effects, as supported by observations in this study. The physiological methods are especially useful as they provide objective markers of the processes and effectiveness of treatment. These observations may help guide further clinical application of yoga in depression and other mental health disorders, and future research on the processes and mechanisms
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